Cortex

Cortex is a server used by VisLab for development purposes (by contrast, the iCubBrain servers are used for demos).

Old information can be consulted at Cortex/Archive.

Specifications

Since summer 2012, there is one machine (cortex1) with these specs:

• 8 x i7-3770K @ 3.50GHz processor
• 16GB of memory (sudo dmidecode --type 17 to see RAM speed and type)
• 112GB SSD drive
• NVidia GeForce GTX 670 graphics card (CUDA)

Operating system installation

In general, follow the guidelines at VisLab machines configuration. Below are some special notes.

Additional software

On this cluster, each user should manage his own yarp and iCub repositories. As a result, do not use system-wide installation of those (sudo make install): instead, simply use make and set your environment variables.

YARP and iCub

The yarp and iCub repositories are installed for user 'icub', similarly to iCubBrain server configuration.

Customization

Network tuning

  sysctl -w net.core.rmem_max=8388608
  sysctl -w net.core.wmem_max=8388608
  sysctl -w net.core.rmem_default=65536
  sysctl -w net.core.wmem_default=65536
  sysctl -w net.ipv4.tcp_rmem='4096 87380 8388608'
  sysctl -w net.ipv4.tcp_wmem='4096 65536 8388608'
  sysctl -w net.ipv4.tcp_mem='8388608 8388608 8388608'
  sysctl -w net.ipv4.route.flush=1

Prompt ($PS1)

The prompt is set to user@cortex?:pwd$ in /etc/bash.bashrc. With those settings, if you log in to Cortex1, the prompt will be user@cortex1:~$. We chose to do so because sometimes it's convenient to have the number of the Cortex machine you're working on embedded in the prompt. By default, though, this configuration is overridden in the users' ~/.bashrc file, and the prompt is set to user@source regardless of the Cortex machine you log in to.
If you want to inhibit this behaviour in ~/.bashrc and thus have a prompt like user@cortex?:pwd, just comment these lines in your ~/.bashrc:

  # set a fancy prompt (non-color, unless we know we "want" color)
  case "$TERM" in
  xterm-color)
      PS1='${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '
      ;;
  *)
      PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w\$ '
      ;;
  esac

However, for users created after 2009-05-07, the prompt is already set to user@cortex?:pwd$ by default.

Mounting network folders

The folder "database" on BlackHole is mounted automatically to /media/blackhole. See /etc/fstab for details.